redirecting URI and passing extra URI...

You can use HTTP::query (Click here) to get the current query string value:

 
 if { [string tolower [HTTP::uri]] starts_with "/freetrial/tabid/121/default.aspx?" } { 
    HTTP::redirect "/FreeTrial.aspx?[HTTP::query]" 
 } 
 

Also, RFC2616 states that the Location value in a redirect must be a fully qualified URL, but most people ignore this as most browsers assume the current protocol and host if one isn't specified.

Aaron